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Thus, the quality requirements as well as mechanical properties of seamless pipes are increasing and becoming more stringent.
It is known that the durability of mandrels depends on their wear resistance during operation, which is one of the most crucial factors affecting the quality of manufactured pipes.
According to [12,13], it is suggested that one of the main factors affecting the service life of mandrels during billets piercing are the billets carbon equivalent and duration of processing.
The results prove that alloying elements addition and content in rolled products shall be deemed as significant factors which essentially affect working tools wear.
Comparison of metal forces affecting the mandrel shows that alloyed chromium and nickel in rolled billets significantly affect the working tools and shall be generally considered as one of the most important factors of the mandrel wear.

As a typical damage mechanism, micro-crack damage have significant effects on the mechanical properties of materials, such as stiffness fall, constitutive anisotropy, strain softening and material fracture[1].
However, due to the hard and brittle properties of the ceramic materials and its microstructure characteristics, lots of researches on the mechanism of crack generation and stress fields have been carried out, and grinding models and stress fields in conventional grinding were established[3-8].
Analysis of Grinding Stress Field Many factors, such as the shape of indenter, the rate of pressure head to the material, the material properties and even external environment, are likely to affect the specific distribution of the stress field.
Due to the direction of pulse force, the larger impact energy generated by ultrasonic vibration is the main factors that the material removal rate of ultrasonic assisted grinding is higher than ordinary grinding.
Peng: Mechanical Engineering, Vol 36 (2000), pp.11

There are wear and vibration problems because of the emitter’s mechanical-scanning-structure.
Under the conditions of the given servo motor and couplings, shaft stiffness and bearing support properties, the dynamic model of the rotor is established as the beam radial bending vibration model, ignoring the influence on bending stiffness of the rotor centerline caused by accessories such as the photoelectric encoder and screws.
Stable external loads along the rotor axis lead to axial preload changes of bearings and affect bearing support stiffness.
Furthermore, these loads affect the performance of rotor dynamics.
Fig.3 Vibration mode of the given configuration Fig.4 (a) First critical speed for different distances between two group bearings; (b) Maximum amplitude for different distances between two group bearings Fig.5 Maximum amplitude for different dynamic unbalance Conclusions Many factors such as rotation speed, rotor material, unbalance, bearing and accessory configurations can affect the rotor system dynamic performance.

Factors affecting the intensity of PbI2 nucleation centers formation from vapor phase remain unknown.
Depending on the influence of each of the listed factors, variety of growth forms of crystals from structurally perfect tapes, plates to bulk crystals of atypical form [7] is observed.
Consequently, considering the negative factors of the impurities influence on the crystallization process and lead iodide properties, in the work is suggested to conduct additional purification of the source components (Pb і І2), and then consistently carry out direct synthesis processes and crystal growth.
This complicates the growth process and negatively affects the homogeneity, structure and properties of the obtained material.
Lyskovich, Wide-band layered crystals and their physical properties, High School.

Differences on composition affect significantly the curvature evolution.
Macroeconomic factors are favoring the growth of the concurrence and world production of this class of products, being constant the search for technological advancement in product and process [1,2].
During the manufacture process of ceramic plates, there are several factors that may affect their planarity.
It is possible to see that at 1200oC both products developed similar properties and typical of glazed porcelain, especially water absorption under 0.5%.
The first one is caused by the mismatch between the physical properties of ceramic tile components in viscous-plastic state.

The relationship between average pressure gradient on pipe and some influence factors (pipe axial velocity, rotating angular velocity, drilling fluid circulation velocity, and axial coordination) was analyzed.
Results showed that average pressure gradient caused by shear stress was only affected by average annular flow velocity, and it didn’t change along pipe length.
From equation (4) and (5), it was noticed that pressure gradient in this model was only related to fluid property and velocity.
But this formula only worked for the model in this paper, the constants in the formula should change when it would be used in other models with different fluid properties or different casing and wellbore with different dimensions.
Determining the Fanning friction factors of power-law drilling fluid flow in pipe and annular, Drilling Fluid & Completion Fluid, 1999(05):4-6

In engineering practice, flow velocity is often the only controllable mechanical index.
In a gas well with high content of hydrogen sulfide, flow velocity is the main factor affecting the deposition of elemental sulfur.
The study of mass transfer between water and hydrocarbon phase indicates that when gas phase coexists with water, the carbon dioxide, hydrogen sulfide, methane, and so on, in the gas phase may be dissolved in the water phase, which may cause a change in gas phase composition and also cause the change of some gas phase properties, thus causing a change of tubing wall corrosion state.
When tubing continuously vibrates, mechanical waves may cause dynamic fracturing at cracks in the tubing.
[8] Wan Xiping, Zhu Jinchuan, et al., (Trans.), The Carbon Dioxide Corrosion Control in Oil and Gas Production—Factors Considered in Design(Petrochemistry Press, China 2002)(In Chinese)

And one of the possible ways of engineering magnetocaloric (MCE) materials is tightly connected with preparing very thin (a few microns) ribbons of high value MCE alloys with good mechanical properties.
In this article we show the results of designing Gd thin foils with the help of cold rolling technique and magnetocaloric properties of such media.
The disadvantage of this approach is that work hardening may affect the magnetocaloric properties of well-characterized bulk materials in an undesirable way.
Next advantage of this approach is good mechanical properties of prepared foils – they are elastic and flexible.
Kuz’min, Factors limiting the operation frequency of magnetic refrigerators, Appl.

Chloride ions activate the passive films on the steel surface and cause corrosion, which leads to the decrease of bearing capacity and cause expansion and cracking of concrete, thus affecting the structural safety and service life, which in fact has become a widespread concern throughout the world and an increasingly prominent problem.
Table 1 Chemical Composition of Cement Clinker and Slag Powder (w/ %) Materials SiO2 Al2O3 Fe2O3 CaO MgO SO3 Na2O K2O LOI Σ Clinker 21.74 5.06 3.56 66.60 0.88 0.81 0.05 0.55 1.26 99.23 Slag Powder 31.39 9.80 1.89 37.90 13.09 0.21 94.28 1.2 Test method The designed strength grade of high volume slag powder concrete is C30, using two kinds of water binder ratio, one is 0.53, the other is 0.42 with the use of water reducer, mixing proportion and the mechanical properties are shown in Table 2.
Therefore, water binder ratio is not a decisive factor for the concrete permeability.
Water binder ratio is not a decisive factor for permeability.
Experimental Research on influencing factors of concrete’s anti-permeability. 

The structural, mechanical and thermal properties of selected samples were studied using X-ray diffraction, scanning electron microscopy, dynamic mechanical analysis, and thermos-gravimetric analysis.
So, the miscible blends allow for valuable properties over the structure range.
It has good mechanical properties and it is more tolerant of the environmental living situation from other transparent polymers[5].
Buang, A review of the properties and applications of poly (methyl methacrylate)(PMMA).
Long, Mechanical and ultimate properties of injection molded cellulose acetate/plasticizer materials.